Apparatus for shaping the ends of can bodies



Aug. l4, 1951 M. R. DELAVAL, BORN CUlZAT APPARATUS FOR SHAPING THE ENDSOF CAN BODIES Original Filed May 15, 1945 Hll Patented Aug. 14, 1951APPARATUS FOR SHAPING THE ENDS F CAN Booms Marie Rene Dela-val, born.Cuizat, Paris, France, assignor to Societe Civile dEtude des BrevetsValac, Paris, France, a corporation of France Original application May15, 1945, Serial No. 593,842. Divided and this application May 23, 1949,Serial No. 95,143.v In France March 28,

Section 1, Public Law 690, August 8, 1946 Patent'expires March 28, 19643 claims. (01. 153-48) This application is a division of my co-pendinapplication Serial No. 593,842, filed May 15, 1945.

for Metallic Box, which application is now abandoned.

Metallic boxes or cans and more particularly cans of cylindrical shapeare already known which comprise a removable stamped lid forced into andfitting a collar applied and secured onto the upper part of the canbody, thus forming a hermetic closure for the can while permitting oneto use the latter again after it has been emptied.

On the other hand, metallic boxes or cans are known, the body of whichis stamped out of a single piece. Such cans offer certain advantages asregards their manufacture and use but they do not lend themselves to adirect application of aforced hermetically closing lid. I

The present invention has for its object a device for the manufacture ofa metallic can or cylinder comprising a body preferably stamped out of asingle piece without any connections or stamped out and provided at itsupper end with a ring crimped unto the body so as to allow a hermeticclosure by means of a stamped lid secured by forcing. v

The provision of a reinforcing ring in the upper part of a stamped canbody through rolling and turning down the rim of the said can asdescribed above constitutes in itself a technical problem the solutionof which does not seem to have been taken into consideration hitherto.

The process used for the manufacture of metal r cans bounded by acylindrical wall with an outside reinforcing ring with the deviceaccording to this invention, consists in forming a bead around the rimof the opening by rolling the outwardly and then forcing the adjacentwall carrying the bead parallel to the main wall of the can so as tomaintain the bead in close contact with the outer surface of the canwall. 7 r

The device for carrying out this process, comprises a die and a punchaxiallymova'ble-with respect to the die to force a can against the die,

said die being provided with an annular groove comprising an inner partof large radius curvature and an outer part of small radius curvaturemerging into a straight wall which groove pro-= duces first the rollingup of the rim into a bead and then the forcing of the adjacent wallcarrying the bead parallel the main wall of the can under the action ofthe displacement of the punch.

According to another feature of the invention the die comprises acompressible core such as a core made of two parts which can slide withrespect to one another against the action of a spri and onto which thebody of the can is applied. The punch is then a hollow punch fittingonto the core of the die.

A form of execution of the above mentioned device is shown by way ofnon-limitative example in the appended drawing in correlation with aform of execution of the reinforcing ring which is also given by way ofnon-limitative example. In this drawing:

Figure l is an elevational view of a box or can made with the deviceaccording to the invention with its lid, the latter being shownseparated from the body of the can.

Figure 2 is a sectional view of the rim of the can on a larger scale.

Figure 3 is a sectional View of a can body provided with a reinforcingrim formed on a separate collar which is fastened to the body through acrimping operation.

Figure 4 is a sectional axial vertical view of the device according tothe invention and Figure 5 is a sectional view of the groove of the saiddevice on a larger scale.

In the example shown in Figure 1, I represents the body of the box orcan which is stamped out of a single piece and comprises a reinforcingring 2 in its upper part. The lid 3 of the can is a stamped cover of anusual type in the rolled rim of which is provided a notch 4 into whicheither a coin or a screwdriver can be introduced for opening the box orcan.

As may be clearly seen from Figure 2 the reinforcing ring 2 is obtainedby turning down the upper rim of the can body on the outside of thelatter. This turned down part offers a profile having the shape of aninverted U and terminates in its lower part in a circular rolled part 0rbead 5 bearing against the wall of the can body, thus insuring a highrigidity.

Figure 3 shows the case of a can of large dimensions the body 6 of whichis provided in its upper part with a collar 1 separately applied andfastened through a crimping of the part 8 and comprising a reinforcingring 2 such as described hereabove.

The device which is used for forming the reinforcing ring 2 on a canbody such as shown in Figures 1 and 2 comprises, in the form in which itis shown in Figure 4, a die 9 secured by means of screws II] on adie-holder II resting on the Working table of the stamping press. Thesaid die comprises a cylindrical central core I2 the outer diameter ofwhich corresponds to the inner diameter of the can body underconsideration and an annular groove I3 around the said core, The grooveI3 (see Figure 5) has a U-shaped profile comprising a rectilinear partI3a forming for a short distance an extension of the generatrix of thecore I2 and followed by a curvilinear part I3b having a comparativelygreat radius of curvature and connected by'a concave conge I30 having asmaller radius of curvature with a rectilinear part I3d parallel to thegeneratrix of the core I2. The depth of the said groove can varyaccording to the depth which it is desired to give to the reinforcingring of the can body.

The core I2 is extended upwards by a sliding core I4 the upper part I iaof which has a diameter which is equal to the diameter of the core I2,i. e. equal to the inner diameter of the can body to be machined orworked upon and the top Mb of which is provided with a hollow having ashape corresponding to that of the bottom of the can body. In its lowerpart the sliding core I4 comprises a cylindrical tench i ic having areduced diameter and slidingly fitting a bore I2-a provided in thecentral core i2 of the die 9 and, furthermore, guided and retained inthe latter by an axial rod i5 screwed into the core Id.

:Finally, the latter is provided with a middle part led the diameter ofwhich is smaller than that of the upper part Mia and around which a coilspring It is arranged which rests, on one hand, onto the core I2 of thedie and, on the other hand, on a shoulder Hie of the upper part Thiscoil spring, the outer diameter of which is slightly smaller than theinner diameter of the can body is preferably constituted by a wire ofsquare section rounded towards the inside. The length of said spring,when not compressed, is such that the distance between the top I ib ofthe sliding core and the beginning of the groove I3 in the die 9 issubstantially equal to the height of the stamped can body before theformation of the reinforcing ring according to the invention and theplay left between the lower part of the tenon I40 and the bottom of thebore Ilia, i. e. the stroke of the sliding core Id, is slightly greaterthan the total developed length of the reinforcing ring to be formed.

Cooperating with the die is a hollow punch II which can be secured tothe tool-holder slide of the press and the inner diameter of which issubstantially equal to the outer diameter of the can body. In the bottomof the said punch is provided a piece-driver la the lower face of whichreproduces the bottom of the can.

The so constituted device works as follows:

The stamped can body (the height of which is, of course, chosensufficiently great to make :it possible to form the desired reinforcingring) is fitted onto the sliding core I i of the machine, whereafter thepunch I'a" is lowered. When the bottom of the can is clamped between thetop I ib of the sliding core and the piece-driver I8 the lowering of thepunch determines a corresponding lowering of the can body and,accordingly, the insertion of the free edge of the wall of the latterinto the groove I3of the die. On arriving against the curvilinear partI3b the said wall is widened out and then it is rolled upon.

itself in the bottom I30 of said groove, thus forming the bead 5 of thereinforcing ring (see Figure 2). When the punch II continues itslowering movementthis rolled part is driven upwards, in the groove I3along the body of the can and the reinforcing ring is thus formed untilthe punch has reached the lower part of its stroke. The punch I1 is thenraised again and the piecedriver I8 insures the expelling of the can.

In order to insure a suitable formation of the reinforcing ring, .theinner surface of the groove I3 should be hardened, rectified andcarefully polished.

WhatI claim is:

1. In apparatus for shaping the upper end of a can body to providethereon an outwardly spaced, annular .re-enforcing ring, terminating atits free edge in a rolled bead which lies within said ring and spacesthe latter in parallel relation to the adjacent wall of the can body, adie member having a central core surrounded by an annular groove, thecross sectional contour of the bottom of the grooves being of compoundcurvature, starting with an outwardly directed portion, with a radius ofrelatively .large curvature, followed by an upwardly directed portionwith a radius of smaller curvature, said curved portions being disposedand connected in a manner to provide a smooth curved die surface andtheir oppositeends respectively terminating in parallel verticalportions which extend tangentially with respect to said ends of thecurved portions.

2. In apparatus for shaping the upper end of a can body to providethereon an outwardly spaced, annular re-enforcing ring, terminating atits free edge in a rolled head which lies within said ring and spacesthe latter in parallel relation to the adjacent wall of the can body; astationary die having an .upstanding central core for supporting a canbody, a hollow punch relatively movable with respect to said die andadapted to fit over said core and can body, an annular shaping groove insaid die surrounding the base of said core for receiving the edge of thecan body to be shaped, the cross sectional contour of the .bottom'ofsaid groove being of compound curvature, starting with an outwardlydirected portion with :a radius-of relatively large curvature, followedby an upwardly directed portion with a radius of smaller curvature,saidcurved portions being disposed and connected in a manner to providea smooth curved die surface and their opposite .ends respectivelyterminating in parallel vertical portions which extend tangentially withrespect to said ends of the curved portions, whereby, when the edge ofthe can body is forced into said groove, a bead is rolled up and thenforced upwardly in the. groove with a portion of the body of the cantoprovide a parallel, spaced reenforcing ring.

3. In apparatus for shaping the upper end of .a can 'body'to .providethereon an outwardly spaced, annular re-enforcing ring, terminating atits free edge in a rolled bead which lies within said ring and spacesthe latter .in parallel relationito the adjacent wall of the can body;a, stationary die having an upstanding central core for support- .ing acan body, a hollow punch relatively movable with respect to said die andadapted to fit first forming-a vertical continuation of the surface ofthe base of the core, then being directed outwardly on a radius ofrelatively large curvature, followed by an upwardly directed portion,

curved on a smaller radius and terminating in a vertical position lyingparallel and in spaced relation to the vertical continuation of saidcore, said vertical portions extending tangentially with respect to theouter ends of the curved portions and said curved portions beingdisposed and connected in a manner to provide a smooth curved diesurface, whereby, when the edge of the can body is forced into saidgroove, a head is rolled up and then forced upwardly in the groove witha portion of the body of the can to provide a parallel, spacedre-enforcing ring.

MARIE RENEE DELAVAL, BORN CUIZAT.

6 REFERENCES CITED The following references are of record in the file ofthis patent:

Number UNITED STATES PATENTS

